Acid Chelating Research Articles

CO2 capture, geological storage, and mineralization using biobased biodegradable chelating agents and seawater.

Geological storage and mineralization of CO2 in mafic/ultramafic reservoirs faces challenges including limited effective porosity, permeability, and rock reactivity; difficulties in using seawater for CO2 capture; and uncontrolled carbonation. This study introduces a CO2 capture, storage, and mineralization approach with the utilization of biobased biodegradable chelating agents and seawater. An acidic chelating agent solution is used to increase effective porosity and permeability through enhanced mineral dissolution. For instance, applying an acidic N,N-Bis(carboxymethyl)-L-glutamate solution to a porous basalt increased effective porosity by 16% and permeability by 26-fold in 120 hours. Subsequently, alkaline chelating agent-containing seawater improves CO2 capture and storage by inhibiting mineralization, thus maintaining injectivity while providing ions for mineralization and further expanding storage space. Last, controlled mineralization is achieved by adjusting chelating agent biodegradation. Promising CO2 storage and mineralization capacities two orders higher than current techniques, this approach reduces required reservoir volume while enhancing efficiency.

Balancing Brightness and Photobasicity: Modulating Excited-State Proton Transfer Pathways in Push-Pull Fluorophores for Biological Two-Photon Imaging.

Push-pull fluorophores with donor-π-acceptor architectures are attractive scaffolds for the design of probes and labels for two-photon microscopy. Such fluorophores undergo a significant charge-delocalization in the excited state, which is essential for achieving a large two-photon absorption cross-section and brightness. The polarized excited state may, however, also facilitate excited-state proton transfer (ESPT) pathways that can interfere with the probe response. Herein, we employed steady-state and time-resolved spectroscopic studies to elucidate whether ESPT is responsible for the pH-dependent emission response of the Zn(II)-selective fluorescent probe chromis-1. Composed of a push-pull architecture with a pyridine ring as the acceptor, the chromis-1 fluorophore core acts as a photobase that promotes ESPT upon acidification. Although the pKa of the pyridine acceptor increases more than six orders of magnitude upon excitation, the photobasicity is not sufficient to deprotonate solvent water molecules under neutral conditions. Rather, the pH-dependent emission response is caused by the pendant bis-isonicotinic acid chelating group which upon protonation facilitates an excited-state intramolecular proton transfer to the pyridine acceptor. A simple permutation of the core pyridine nitrogen from the para- to the ortho-position relative to the thiazole substituent was sufficient to reduce the excited-state basicity by two orders of magnitude without compromising the two-photon excited brightness. These results highlight the importance of choosing the appropriate fluorophore core and chelating moiety for minimizing pH-dependent responses in the design of fluorescent probes for biological imaging.

Supramolecular architectures, Hirshfeld surfaces analysis, spectroscopic, computational and photovoltaic properties of nickel(II) binary and ternary complexes of N-phenethyl-iminodiacetate (2-) chelate

The bluish-green color nickel(II) binary and/or ternary compounds have been isolated from the solution of stoichiometric reaction between Ni(II) hydroxy-carbonate and N-phenethyl-iminodiacetic acid (H2pheida) chelating ligand in aqueous media with compound (2); [Ni(pheida)(Him)3]·4H2O and without imidazole compound (1); [Ni(pheida)(H2O)3]. The crystal pattern of binary compound [Ni(pheida)(H2O)3] (1) differs from the related tetra-hydrated ternary complex of [Ni(pheida)(Him)3]·4H2O (2) can be attributed to the presence of stronger N-(Him) spacer of imidazole ligand. The compounds reported herein, have been characterized by means of elemental analysis, FTIR, UV–vis, TGA and X-ray crystallography. Moreover, the distinctive inter-molecular forces particularly H-bonding interactions, 2D fingerprint plots and supramolecular architecture have been studied using Hirshfeld surface analysis. The nickel(II) binary and ternary complexes (1) and (2) show distorted octahedral geometry around the Ni(II) ion of the type 1 + 2 + 2 + 1 imposed by 3d8 electronic configuration with degenerate fully and half occupied t2g6 and eg2 orbitals respectively. The higher John-Teller distortion has been observed for complex (2) than that of complex (1). The IDA arm of chelate adopted fac-NO2 conformation in both complexes (1) and (2). Moreover, the photovoltaic properties as semiconducting nature for ligand and their corresponding Ni(II) complexes were estimated using Tauc’s equation, αhν = A(hν-Eg)r, where r = ½ for indirect and 2 for direct electronic transitions through UV–vis absorption data. The indirect and direct electronic transition bandgap (Eg) calculated for complex (1) is 2.0 and 3.07 eV respectively. Similarly, 2.55 and 4.39 eV respectively measured for complex (2).

Poly-γ-glutamic acid chelates chromium (III) and copper (II), alleviating their toxicity in cucumber and affecting rhizosphere bacterial community assembly.

The accumulation of chromium (Cr) and copper (Cu) in soil during industrialization and modernization poses an extreme threat to crops. Poly-γ-glutamic acid (γ-PGA) has the potential to stabilize heavy metals in soil through chelation because of the numerous carboxyl groups in its side chain. The rhizosphere microbiome contributes to plant detoxification by participating in heavy metal passivation. However, it is still unclear whether γ-PGA can alleviate the toxicity of Cr and Cu to plants and whether this effect is associated with changes in the rhizosphere microbiome assembly. Here, we found that γ-PGA application significantly reduced the content of Cr or Cu in cucumber plants by 67.45%-86.77% and 94.67%-98.21, respectively, and alleviated the oxidative stress of Cr or Cu to plants. Moreover, γ-PGA significantly increased the biomass of cucumber fruits in the plot experiment by 13.5% and 25.3% under Cr and Cu stress, respectively. The content of Cr or Cu in the cucumber fruit was below limits of detection, in contrast to the 31.23 mg/kg Cr or 9.86 mg/kg Cu detected in the no-γ-PGA treatment. γ-PGA effectively chelated Cr and Cu in vitro, and less than 30% of their chelates were degraded in 20 weeks, suggesting the strong stability of these chelates. γ-PGA significantly altered the rhizosphere bacterial community composition of cucumber by enriching phyla Gemmatimonadota, Acidobacteriota and Firmicutes, and genera Gemmatimonas and Stenotrophomonas, which potentially involved in reducing the mobility of Cr and Cu in soils. Furthermore, γ-PGA significantly enriched taxa assigned to plant growth-promoting bacteria (PGPB). Together, our results suggest that γ-PGA can reduce the Cr and Cu contents in cucumber, and this process is strongly associated with the chelation capacity of γ-PGA and its effects on rhizosphere microbiome composition. These results highlight the exciting potential to use γ-PGA for the remediation of heavy metal-contaminated soils.

Selection and immobilization of the optimal phytase-producing probiotic: a comparative in silico analyses of five autochthonous lactic acid bacteria

Phytic acid and its salts are the major storage form of both phosphate and myo-inositol, especially in cereals. Phytic acid chelates multivalent cations, which decreases the solubilized form of these nutrients and their dietary bioavailability for absorption and assimilation. Increasing micronutrient bioavailability from the economic phytate-rich food can be achieved by subjecting this food to fermentation by phytase-producing bacteria. A total of 8 lactic acid bacteria were isolated from different fermented food samples. Among the bacteria tested for their ability to produce phytase, only five isolates were selected as promising producers. The results revealed that isolate No. 4 produced the highest phytase levels of 411 U/mL. The five isolates were differentially able to tolerate acidic, alkaline, heat, surfactant, osmotic, bile, and pancreatic enzyme stresses, with the superiority of isolate No. 4, which demonstrated the most desirable probiotic potentials as confirmed by principal component analysis (PCA), heat map, and network analysis. Isolate No. 4 was identified by 16S rRNA sequencing and later confirmed as Pediococcus pentosaceus strain NMP4762Ch under the accession number MZ413646. Moreover, the active cells of P. pentosaceus were immobilized in alginate; the reusability of the immobilized active cells resulted in continuous production with an optimum phytase activity of 432.0 U/mL after 14 days, which decreased with time to reach 142.5 U/mL after 56 days. The maximum shelf stability was also observed, 557.5 U/mL, after 14 days and declined with time, reaching 133.5 U/mL by the end of the 56th day. Since humans don’t naturally produce phytase, utilizing probiotics for phytase production is important to combat mineral deficiencies.

The effect of the composition of hepatoprotective action on biochemical and morphostructural changes in the body of laying hens under thermal stress

To reduce the negative effects of hyperthermia on the body of farm animals and poultry, various drugs and feed additives are currently used. Which do not have sufficiently adaptogenic and antitoxic properties. We studied the effect of a hepatoprotective composition consisting of dried live yeast, amorphous silicon dioxide, propylene glycol, calcium propionate, ascorbic acid, manganese, copper and zinc chelates, methionine and choline chloride on the variability of biochemical and morphological parameters of the body of laying hens under temperature stress. It was simulated by increasing the air temperature in a building where laying hens were kept from 18.0 ± 1.0 °C to 28.0 ± 1.0 °C for 48 hours. Due to hyperthermia, changes in biochemical and morphofunctional parameters were observed in the tissues and organs of birds. The obtained values of the biochemical parameters of blood serum in the birds of the control group indicated the intensity of the adaptive capabilities of their body. A complex of morphological changes confirmed a violation of protein metabolism and the regenerative-compensatory process. Pathological changes in the structure of the duodenum, characteristic of catarrhal-necrotic duodenitis, were identified. The stress reaction was also reflected in the condition of the heart muscle, in which an inflammatory process developed against the background of granular dystrophy of cardiomyocytes. The results of biochemical studies of blood serum in birds of the experimental group indicated an increase in the anti-stress response to a temperature stimulus under the influence of the studied composition (tendency to increase glucose and calcium, increase alkaline phosphatase activity by 47.4 %). The introduction of a hepatoprotective composition into the diet of laying hens during periods of temperature stress did not lead to disruption of the structure of tissues and organs, preserving cellular metabolic mechanisms. The

Roles of Exogenous 5-Aminolevulinic Acid and Dihydroporphyrin Iron in Chlorophyll Precursor Synthesis and Chlorophyll-Related Enzyme Activities in Wheat Under Different Light Intensities

Aminolevulinic acid (5-ALA) and dihydroporphyrin iron chelates (DHFe) play roles in plant growth regulation under normal and stressful conditions. However, definitive data on their roles in regulating chlorophyll synthesis in wheat are lacking. In this study, the optimal concentrations for foliar-spray application of 5-ALA and DHFe to promote wheat seedling growth and leaf chlorophyll content were assessed. The optimal concentrations of 5-ALA or DHFe (50 mg/L and 0.01 mg/L, respectively) were applied as foliar sprays to seedlings of wheat ‘Bainong 4199’ (high light efficient) and ‘Zhoumai No. 18’ (average light efficient) under different light intensities. Chlorophyll precursor contents and activities of three chlorophyll synthesis-related enzymes were altered, and the combined application of 5-ALA and DHFe more strongly increased the leaf chlorophyll content. 5-ALA significantly increased the contents of the chlorophyll precursors porphobilinogen, uroporphyrinogen III, protoporphyrin IX, and magnesium-protoporphyrin IX, and the activities of 5-amino-ketovalerate dehydratase and uroporphyrinogen III synthase. DHFe resulted in an increase in chlorophyll content but a significant decrease in chlorophyllase activity and protochlorophyllide content. 5-ALA promoted the synthesis of chlorophyll precursors by regulating the activities of 5-amino-ketovalerate dehydratase and uroporphyrinogen III synthase. DHFe decreased chlorophyllase activity, thereby slowing chlorophyll degradation and increasing the chlorophyll content.

Stable Cu (I) Complexes for Intracellular Cu-Catalyzed Azide Alkyne Cycloaddition.

The copper-catalyzed azide-alkyne cycloaddition (CuAAC) has heralded a new era of chemical biology and biomedicine. However, caveats of CuAAC include formation of reactive oxygen species (ROS) and other copper-related toxicity. This limits utility in sensitive biological samples and matrices. Towards addressing these caveats, we synthesized and fully characterized two air and water stable trinuclear Cu (I) dimer complexes. The complexes were stable to oxidation in the presence of hydrogen peroxide, acid, base, and other chelators, which was reasoned to be due to the linear benzimidazole-Cu-benzimidazole geometry. Computational investigations of the catalytic cycle implicated two of the three coppers in the trimer complex as the active metal centers. The complexes were shown to catalyze the reaction at far below sub-toxic concentrations for intracellular click reactions to label triple negative breast cancer cells and compared to the current CuSO-4-THPTA standard.

Comparison of Essential Oils of Schinus molle L. Leaves Growing in Different Regions of Algeria in Terms of Their Chemical Compositions and Various Biological Activities

ABSTRACTThis preliminary study investigated the chemical composition and biological properties of essential oils derived from Schinus molle L. leaves obtained from three specific regions in Algeria: Algiers (SMA), Djelfa (SMD), and Mascara (SMM). Gas chromatography (GC) and Gas chromatography–Mass Spectrometry (GC–MS) analyses confirmed the presence of 52 compounds (100.0%) in SMA essential oil, 50 compounds (100.0%) in SMD, and 72 compounds (100.0%) in SMM essential oils. The main components of SMA oil were camphene (31.82%), limonene (14.71%), and p‐cymene (9.25%). In SMD and SMM oils, α‐phellandrene (14.25% and 12.70%), limonene (13.02% and 11.90%), and germacrene D (10.62% and 10.15%) were the major components, respectively. The antioxidant characteristics were evaluated using five methods: β‐carotene‐linoleic acid, DPPH, ABTS+, CUPRAC, and Metal chelating assays. The results revealed a moderate to low anti‐oxidant effect, with SMA essential oils exhibiting the highest activity. A moderate inhibitory effect against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α‐glucosidase, α‐amylase, urease, and tyrosinase was observed, indicating anti‐enzymatic activity. Nevertheless, all samples had higher IC50 values for both antioxidant and anti‐enzymatic activities than 200 μg/mL. It was determined that regional differences in the locations where S. molle grows showed both qualitative and quantitative differences in essential oil components. This difference was also detected in the biological activities of the essential oils. The anti‐inflammatory capacities of the three samples were assessed using Human Red Blood Cell (HRBC) membrane stabilisation and egg albumin denaturation techniques. The results showed effective anti‐inflammatory activity in all three samples. The antimicrobial efficacy was evaluated using a range of tests, such as anti‐quorum sensing, violacein inhibition, anti‐swimming, and anti‐swarming assays, demonstrating moderate activity. No toxic effects were observed at the tested dosages when assessing cytotoxicity against a healthy cell line (CCD18‐Co). This thorough examination provides valuable insights into the chemical composition and bioactive properties of essential oils derived from S. molle. These findings indicate the possible use of these essential oils in the food, medicinal, and cosmetic industries.

Optimized Lithium(I) Recovery from Geothermal Brine of Germencik, Türkiye, Utilizing an Aminomethyl phosphonic Acid Chelating Resin

ABSTRACT This study investigates the performance of Lewatit TP 260 ion exchange resin for the efficient recovery of lithium (Li(I)) from geothermal water sourced from the Germencik Geothermal Power Plant in Türkiye. A series of batch sorption experiments were performed to evaluate the influence of key parameters, including resin dosage, solution pH, temperature, initial Li(I) concentration, and contact time, on the Li(I) recovery process. The optimal conditions were determined to be a resin dose of 0.5 g per 25 mL of geothermal water, pH in the range of 6–8, and a temperature of 25°C. Under these conditions, the resin achieved a maximum Li(I) recovery rate of 71% from the geothermal water. Sorption isotherms were further analyzed using the Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) models. Among these, the Langmuir model provided the best fit (R² = 0.9841), suggesting a maximum sorption capacity (qm) of 4.31 mg/g. Continuous recovery experiments conducted in column mode confirmed the practical applicability of Lewatit TP 260, achieving a total sorption capacity of 0.41 mg Li(I)/mL resin. The findings exhibit the potential of this resin as a viable sorbent for sustainable Li(I) extraction from geothermal brines, supporting the development of green energy technologies and contributing to the circular economy.

Cutaneous Manifestations of Liver Disease: A Narrative Review.

Chronic liver disease is a major cause of morbidity and mortality. The most common extrahepatic manifestations are dermatological. The pathophysiology of these dermatological manifestations is not clear, but it is postulated that the mechanisms involved include generalized vasodilatation, hyperdynamic blood circulation, and altered estrogen metabolism. The most common cutaneous manifestations of liver disease are Terry's nails and pruritus. Terry's nails consist of leukonychia with a distal pink band and the absence of the lunula. The main differential diagnosis is Lindsay's nails. Vascular manifestations of liver disease include palmar erythema and arachnoid nevi, the latter located in the vascular territory of the superior vena cava and occurring in chronic alcohol-associated liver disease. Dermatological manifestations generally resolve with improvement or remission of liver disease, and there is no specific treatment for them. However, bile acid chelators are the first line of treatment for cholestatic pruritus. Studying dermatological manifestations of liver disease contributes to early diagnosis and treatment, potentially improving the patient's prognosis.

Enhanced oil recovery and mitigating challenges in sandstone oil reservoirs employing EDTA chelating agent/ seawater flooding

While low salinity water (LSW) holds promise for improving oil recovery, its implementation is comparatively costly due to the substantial volumes of fresh water required to dilute seawater (SW). Additionally, concerns arise regarding potential issues related to LSW, including fines migration in sandstone reservoirs and scale formation in carbonate reservoirs. Chelating agents can be introduced into undiluted SW to bind with metal ions, thereby lowering its salinity. This approach mimics the behavior of LSW injection while overcoming associated challenges. This study involves measuring oil/injected solution interfacial tension (IFT), evaluating sandstone surface wettability alteration, along with conducting different sand pack flooding scenarios using Ethylenediaminetetraacetic acid (EDTA) chelating agent. The aim was to comprehend the EDTA oil recovery mechanisms and determine the optimal concentration of EDTA that minimizes chemical consumption while maximizing oil recovery. The findings indicated that incorporating 5 wt% EDTA into SW significantly reduced IFT from 29.52 mN/m to 4.75 mN/m, making the oil nearly miscible in the solution. Moreover, wettability tests confirmed that a minimum EDTA concentration of 5 wt% is required to shift wettability from oil-wet to strongly water-wet conditions. Sand pack flooding experiments, on the other hand, further demonstrated that this optimized fluid system can potentially recover an additional 16.1 % of oil following SW flooding. Finally, inductively coupled plasma (ICP) analysis revealed a notable increase in metal ion concentration during EDTA flooding, indicating enhanced leaching of metals from the sandstone surface and improved wettability characteristics.

Chelator-impregnated polydimethylsiloxane beads for the separation of medical radionuclides

Chelator-impregnated resins have been studied earlier for the chemical separation of elements in aqueous solutions, but issues with their chemical stability have limited their use in the separation of (medical) radionuclides from their respective irradiated targets. We developed a polydimethylsiloxane (PDMS)-based chelator-impregnated resin that showed a high chemical stability against leaching. Several different chelators were tested in this study. After impregnation of the PDMS beads with the di-2-ethylhexylphosphoric acid (D2EHPA) chelator, an in-flow separation study with various radionuclides (Y-90, La-140, and Ac-225) was conducted. These three radionuclides have potential use in nuclear medicine and a production route through irradiation of Sr-, Ba-, and Ra-targets respectively, necessitating their chemical separation. The D2EHPA-impregnated beads achieved high adsorption efficiencies of 99.89% ± 0.14%, 99.50% ± 0.10%, and 98.51% ± 0.25%, for Y-90, La-140, and Ac-225, respectively, while co-adsorption of minor amounts (<3%) of the targets were reported. These results, together with the high chemical stability of the PDMS-based resin, highlight the potential of chelator-impregnated resins in the rapidly growing field of (medical) radionuclide production.

Bivalent affinity binding-inspired PPARγ immobilization with selective conformation and improved ligand-binding activity

Functional protein immobilization forms the basis for bio-detections. A series of one-point, site-specific immobilization methods have been developed, however, it still remains as a challenge how to avoid the proteins to move in all directions as well as conveniently regenerate the bio-devices. Herein, we have developed a bivalent affinity binding-inspired method for PPARγ immobilization using DNA aptamer and nickel-nitrilotriacetic acid (Ni2+-NTA) chelation. The specific DNA aptamer (Apt 2) was selected by an on-column systematic evolution of ligands by exponential enrichment (SELEX) method with affinity of (1.57 ± 0.15) × 105 M−1, determined by isothermal titration calorimetry (ITC). Apt 2 and nickel-nitrilotriacetic acid (Ni2+-NTA) were modified on macroporous silica gels via L-α-allylglycine as a linker. They respectively interacted with PPARγ and 6×His tag via bivalent affinity binding for the receptor immobilization. After comprehensive surface characterization, PPARγ was proved to be successful immobilized. Chromatographic studies revealed that the immobilized PPARγ has conformation selectivity, which discriminated agonist and antagonist of the receptor. Ligand-binding parameters (affinity and rate constant) of four agonists (rosiglitazone, pioglitazone, troglitazone, and magnolol) with PPARγ were determined. Troglitazone showed the lowest dissociation rate constant. The binding affinities (3.28 × 107, 1.91 × 106, 2.25 × 107, and 2.43 × 107 M−1) were highly consistent with the data obtained using purified receptor in solution (2.16 × 107, 4.52 × 106, 1.20 × 107, and 1.56 × 107 M−1), offering reliable bio-detection method for PPARγ and its ligands. Due to the biocompatibility of nuclear receptor with DNA, it is conceivable that the bivalent affinity-based method will be a general method for the immobilization of other nuclear receptors, which may provide selective conformation and improved ligand-binding activity for the receptors.

Synthesis, spectral investigation, biological efficacy, and computational evaluation of the hydroxamic acid chelator and its Zn(II) metal complex with potent anticancer activity

Synthesis, spectral investigation, biological efficacy, and computational evaluation of the hydroxamic acid chelator and its Zn(II) metal complex with potent anticancer activity

Catalase catalyzed tannic acid-Fe3+ network coating: A theranostic strategy for intestinal barrier restoration

Epithelial barrier impairment of intestinal inflammation leads to the leakage of bacteria, antigens and consequent persistent immune imbalance. Restoring the barrier function holds promise for management of intestinal inflammation, while the theragnostic strategies are limited. In this study, we developed a novel coating by catalase (CAT)-catalyzed polymerization of tannic acid (TA) and combined chelation network with Fe3+. TA-Fe3+ coating was self-polymerized in situ along the small intestinal mucosa, demonstrating persistent adhesion properties and protective function. In enteritis models, sequential administration of TA-Fe3+ complex solution effectively restored the barrier function and alleviated the intestinal inflammation. Overexpressed CAT in inflammatory lesion is more favorable for the in situ targeting growth of TA-Fe3+ coating onto the defective barrier. Based on the high longitudinal relaxivity of Fe3+, the pathologically catalyzed coating facilitated the visualization of intestinal barrier impairment through MRI. In conclusion, the novel TA-Fe3+ delivery coating proposed an alternative approach to promote theranostic intervention for intestinal diseases.

Carbon nanotubes-encapsulated Co/Co7Fe3 nanocomposites: Achieving wideband electromagnetic wave absorption at ultrathin-thickness by regulating magnetic phase ratio

Nowadays, through various strategies such as composition regulation and structural design, the electromagnetic wave (EMW) attenuation ability of composites has been significantly improved. Nevertheless, at ultra-thin sample matching thicknesses, it is still a challenge for absorbing materials to possess high-intensity and wide bandwidth simultaneously. In this work, the cobalt/iron nitrilotriacetic acid chelates (Co/Fe-NAC) were fabricated by a one-step hydrothermal self-assembly strategy. Then, a series of carbon nanotubes-encapsulated Co/Co7Fe3 (Co/Co7Fe3@CNTs) nanocomposites were constructed by coating glucose hydrothermal carbon on Co/Fe-NAC precursors and subsequent calcination process. By controlling the Co/Fe ion content, the magnetic phase ratio in the product can be efficiently regulated to comprehensively optimize microwave absorption (MA) performance. The minimum reflection loss (RL) of the optimized sample is −42.6 dB at only 1.1 mm thickness, and the effective absorption bandwidth (EAB) reaches up to 10.1 GHz (7.9–18 GHz). Surprisingly, for all samples, the widest EAB can exceed 8.2 GHz at the ultra-thin thickness (thinner than 1.3 mm) and the strongest RL values are all below −30 dB (99.9 % EMW can be absorbed). Such excellent MA performance is attributed to the strong magnetic loss of highly dispersed magnetic nanoparticles, the strong dielectric properties of carbon nanotubes and shells, optimized impedance matching, as well as the synergistic effect of multi-dimensional heterogeneous components and structures. Moreover, the high-frequency structure simulator (HFSS) was used to further analyze the multi-polarization behaviors and heterogeneous magnetic coupling effect. This work may provide a new direction to the fabrication of efficient and ultra-thin absorbers, and Co/Co7Fe3@CNTs nanocomposites may become a promising candidate for practical application in the MA field.

Taylor dispersion analysis for measurement of diffusivity and size of gadolinium-based contrast agents

Gadolinium-based contrast agents (GBCA) are complexes of a Gadolinium metal center and a linear or macrocyclic polyamino-carboxylic acid chelating agent. These agents are employed to enhance the visibility of deep abnormalities through MRI techniques. Knowing the precise dimensions of various GBCA is key parameter for understanding their in-vivo and pharmaco-kinetic behaviors, their diffusivity, as well as their relaxivity. However, conventional size characterization techniques fall short when dealing with these tiny molecules (≤1 nm). In this work, we propose to determine the size and diffusivity of gadolinium-based contrast agents using Taylor dispersion analysis (TDA). TDA provided a reliable measurement of the hydrodynamic diameter and the diffusion coefficient. The obtained results were compared to DOSY NMR (Diffusion-ordered Nuclear Magnetic Resonance Spectroscopy) and DFT (Density Functional Theory).

Characterization of Polysaccharide Extracts of Four Edible Mushrooms and Determination of In Vitro Antioxidant, Enzyme Inhibition and Anticancer Activities.

Mushroom polysaccharides are important bioactive compounds derived from mushrooms with various beneficial properties. In this study, the chemical characterization and bioactivities of polysaccharide extracts from four different edible mushrooms, Clavariadelphus truncatus Donk, Craterellus tubaeformis (Fr.) Quél., Hygrophorus pudorinus (Fr.) Fr., and Macrolepiota procera (Scop.) Singer were studied. Glucose (13.24-56.02%), galactose (14.18-64.05%), mannose (2.18-18.13%), fucose (1.21-5.78%), and arabinose (0.04-5.43%) were identified in all polysaccharide extracts by GC-MS (gas chromatography-mass spectrometry). FT-IR (Fourier transform infrared spectroscopy) confirmed the presence of characteristic carbohydrate patterns. 1H NMR suggested that all polysaccharide extracts had α- and β-d-mannopyranose, d-glucopyranose, d-galactopyranose, α-l-arabinofuranose, and α-l-fucopyranose residues. Approximate molecular weights of polysaccharide extracts were determined by HPLC (high-performance liquid chromatography). The best antioxidant activity was found in M. procera polysaccharide extract in DPPH• (1,1-diphenyl-2-picrylhydrazyl) scavenging (39.03% at 800 μg/mL), CUPRAC (cupric reducing antioxidant capacity) (A0.50: 387.50 μg/mL), and PRAP (phosphomolybdenum reducing antioxidant power) (A0.50: 384.08 μg/mL) assays. C. truncatus polysaccharide extract showed the highest antioxidant activity in ABTS•+ scavenging (IC50: 734.09 μg/mL), β-carotene-linoleic acid (IC50: 472.16 μg/mL), and iron chelating (IC50: 180.35 μg/mL) assays. Significant anticancer activity was found in C. truncatus polysaccharide extract on HT-29 (IC50: 46.49 μg/mL) and HepG2 (IC50: 48.50 μg/mL) cell lines and H. pudorinus polysaccharide extract on the HeLa cell line (IC50: 51.64 μg/mL). Also, H. pudorinus polysaccharide extract possessed prominent AChE (acetylcholinesterase) inhibition activity (49.14% at 200 μg/mL).

Antioxidant and immunomodulatory potential of cell wall polysaccharides from Harungana madagascariensis Lam

Numerous plant polysaccharides have demonstrated immunomodulatory and antioxidant potentials, and can be investigated as novel molecules with biological properties that may enhance immune function. The aim of this study was to assess the antioxidant and immunomodulatory properties of cell wall polysaccharides fractions isolated from Harungana madagascariensis (HM). Pectin fraction (PF) and hemicellulose fraction (HCF) were extracted and tested for their antioxidant properties using reducing power, 1,1-diphenyl-2-picryl hydrazyl (DPPH) and 2,2′-azino-bis-3-éthylbenzylthiazoline6-sulphonic acid (ABTS) radical scavenging assays, chelating activity and inhibition of lipid peroxidation. Their immunomodulatory activities were carried out on peritoneal macrophages targeting NADH oxidase and lysosomal enzyme activities as well as the production of nitric oxide (NO) and hydroperoxides (H2O2) during phagocytosis of Saccharomyces cereviceae. The polysaccharides fractions showed significant antioxidant and immunostimulatory activities via stimulation of NADH oxidase and lysosomal enzyme of peritoneal macrophages and production of NO and H2O2. Taken together, the results of this study indicate the potential of polysaccharides from H. madagascariensis as antioxidant and immunomodulator agents.